Could I perform as good as Actuate?
I am not sure, Actuate is very well written and Joshua Granick has been working on it for a long time and tested it extensively.
But I probably could improve on my code and get a better performance in Flash (in which I did the stress-test). The downside is that my code will be full of condition compilation and that would mean the code would become more and more complex.

Why am I sure it will improve, well I cheated and did some flash specific code modifications.
Check the code in github
In my first draft it was just:

So the question is more do I want to change the code for specific platforms?
For now I am not going to focus on Flash to enhance it’s performance… there is little chance that I will be animating 1000+ objects.

So I will be using it in my own projects and will run into problems that I will fix.
You are welcome to use it as well and report bugs or other improvements.

I’ve update the promotional website: check it here.
You can find the stress-test there, where I compare Go with Actuate.
If you want to add your tweening library, add it here in github.
Download/install instructions can be found here.